[ppurcell]

Greetings all,

I am setting up a new 75G reef and am using 5" of 1-2mm aragonite sand bed with a 1.25" plenum. Sitting on top of the sand bed, I have roughly 120-150lbs of base rock with minimal contact to the bed surface. (was LR, but was put into storage for around a year).

I also have a small 2 gallon wet/dry fed by an overflow box, followed by a double baffle for carbon bags before water enters the main section of the sump where I have a medium size protein skimmer of an unknown type. The sump is my old 55 gallon aquarium which I drilled and seems to be working adequately as I have 0Am/ 0Ni/ 0Na with a modest bio load.

So, after all the pre-amble, I would like to solicit opinions on two things.

1. Should the mechanical (except for very course mech) and chemical filtration before the protein skimmer be removed?

2. Is is inappropriate to use a wet/dry in tandom with a live sand bed? If so, what makes the two systems antagonistic?


Best regards,

Phillip Purcell

[BubbaWPB]

1. I always like to have some sort of mechanical filter to sift out the big chunks of fish poo, leftovers, and other detruitus before it can lodge in some part of the tank and decompose. I use a bag filter. I use charcoal after the protein skimmer because I run ozone through the protein skimmer. I really don't think it matters if the charcoal is before or after. I like the filter bag before the skimmer so I don't have to clean the "stuff" out of the skimmer as often.

2. It is not inappropriate to use the wet/dry with your setup, but it is just totally unnecessary with 2 pounds per gallon of live rock... and a deep sand bed... and a plenum. They are not antagonistic, just redundant.

[charlie]

2. It is not inappropriate to use the wet/dry with your setup, but it is just totally unnecessary with 2 pounds per gallon of live rock... and a deep sand bed... and a plenum. They are not antagonistic, just redundant.

Well said!!!!!

[ppurcell]

Thanks for the reply, I guess my 2nd question would have been better if I had asked if the wet/dry and the DSB are complimentary, redundant or antagonistic. I wasn't sure and it's a trivial thing to remove the media from the wet/dry. Anyhow, it is working for now. Seems that bio balls in general have developed a negative reputation in reef tanks because:

1. They get gunked up (mine never seem to)
2. They promote nitrate accumulation (ok, water changes, dsb, nitrate reactor, etc)

I read some comments from Anthony Calfo @WWM where I thought he was saying that it was better to provide little or no mechanical or chemical filtration before the PS as the mechanical will provide the opportunity for adding increased dissolved organics as the trapped matter decomposes if not removed rapidly. And that the chemical should follow the PS, which would clean out some of the pollutants not filtered by the skimmer. This would seem to increase the ammount of skimmate per day as you say, but conversely it would also appear to reduce the nitrogen load on the system. It would also add to the life of the chemical media as much of what it would have absorbed would be in the skimmers collection cup.

Anyhow, pehaps the differences aren't significant. I'm not sure, which is why I posted...

Best Regards,

Phil

[Steven Pro]

Mechanical filters are only good if you are militant about their maintenance. They can be an exceptionally good nutrient export mechanism if you clean/replace them everyday. Few people have the time and dedication to do this. If you don't, they contribute to nitrates.

I would agree with Anthony that raw, unfiltered water is best for the protien skimmer. After that, additional chemical or biological filtration can be placed such as activated carbon, phosphate removers, or refugiums.

Unless you have a heavy bioload, as inthe case of a predator tank, wet/dry trickle filters are usually unnecessary.

[ppurcell]

Ok, I'm convinced, I removed the bio balls from the WD. It's been 2 days and AM/NI/NA are still reading 0. I'll keep testing...

Also constructed an above tank 20G Refugium for my 75 display tank. I am considering dividing the tank floor 80/20 with the 80% side as another DSB using sugar fine aragonite and the 20% side with 4-6mm aragonite for 'pods. I plan to grow Gracilaria for nutrient export under 4x23W PC's. Any thoughts if this seems like a reasonable plan? I'm not quite sure how much water flow I should direct through this configuration; I've read all kinds of numbers ranging from 4-15 times tank volume. My current pump can manage about 10X. What is the best method of feeding the plankters which will be growing and developing in the refugium? I've seen plankton reactors, are they necessary?